Warm Neutral Opaque Photo Black Shade 1 as a universal black


#1

I don’t understand why IJM doesn’t promote Warm Neutral Opaque Photo Black Shade 1 as a universal black to a greater extent. It’s true that it gets a mention, e.g. on page 5 of the new Piezography Manual, and it was Jon who first recommended it to me here. But given its potential I’m surprised that it doesn’t get more profile as a universal black. E.g. the main source for this claim still seems to be Mark Sonners’ original statement back on the old Yahoo forum. I’d have thought that a dedicated page on IJM was warranted, e.g. under Product Manuals and Instructions. I.e. something authoritative that we could refer people to, rather than cobbling together a series of older posts from a moribund forum.


#2

Ok, now I’m confused. I’ve just seen this post on the Yahoo Digital B&W forum:
https://groups.yahoo.com/neo/groups/DigitalBlackandWhiteThePrint/conversations/messages/108275

The numbers in this post seem to contradict what Jon told me here 18 months ago, which was to use WN Opaque as a universal black. Tyler Boley also recommended it in various places. Now we’re being told to use Selenium Shade 1 as a universal. What gives?

This is precisely the sort of disparate and, on this occasion, conflicting information that we were commenting on in that documentation thread.

p.s. I posted some dmax numbers on that Yahoo thread for WN Opaque 1 that are a lot higher than what Jon posted. This time I really did print out a series of 14 x 100% patches in calibration mode shade 1 and took the average. The numbers are improving as the page dries (no hairdryer access right now), but they’ve already climbed to 1.641.


#3

We do not really push a Universal Black because it is confusing in that Epson printers have two slots. Further, Piezography does not print with much black ink and there is little gain between using SEL1 or WN1 when you use a K7 or K6 curve. If you study one you will see that most of the dMax is the result of 3 or 4 inks rather than just one ink as is customary with StudioPrint or QTR. Take a read here:

http://www.piezography.com/PiezoPress/blog/piezography-technical/black-is-black/

It’s not the dMax of the black, but what you do with it that counts.
If you want black that is knocked out of the park, you would have to give up a lot of shadow detail or have a tremendous amount of pixel value 0 in your images and very little pixel value 0 is usually in an image file that has a full range of tone.

As a universal black in which you will use matte / glossy from one - the Selenium will give more dMax on matte and the Warm Neutral will give more on glossy. So choose yours.

Jon


#4

I confess that I hadn’t seen that black is black article. Again, as per the comments on that documentation thread, the information is all out there, but finding it is a challenge and an archaeological dig. I just subscribed to that blog so as not to miss any more of these.

That info is what I’m looking for. However I hesitate to say this, given how little I know, but I don’t believe the WN Opaque 1 number of 1.409 on HPR. Are you sure about this? I just did this test, and after a night of drying my measurement is now at 1.660. And that’s without making any allowance for density drop-off from overloading, as pointed out elsewhere by Richard Boutwell. My number is broadly consistent with what Tyler and Mark Sonners reported, but yours is not.

Are you really saying that there’s such a difference between this ink and the other shade 1’s? What would cause this? Based on my measurement, WN Opaque 1 is pretty much exactly the same as Selenium 1 (your measurement of 1.661), and as WN 1 is better on gloss I think it’s the clear choice.

Yes, I understand that in practice printing 100% black using a piezo curve will combine quite a few shades. On my printer it uses four with perhaps a touch of shade 5. I understand that not much of shade 1 is used, so its impact is minor. I understand that piezography printing is all about open shadows and shadow detail. And retaining shadow detail on gloss can be a challenge, given its greater dmax. But if we’re going to go to the trouble and (minor) expense of switching inks then I’d like to know that there’s some (minor) benefit, and right now I can’t see it.

I personally don’t think that a universal black is confusing, and I see a marketing opportunity.


#5

what lot # do you have for WN1?
we can check again on our side.


#6

Batch # 1000809
Expiry: 09/2015

When measuring density I often find that there is sample variation. When I print the 21x4 chart for checking linearity and creating soft-proof ICCs, I have a little spreadsheet I created to check the consistency between four readings of each of the 21 patches. Aberrant readings do happen, and if you’re relying on a single reading then it’s more of a risk. Although that said, in my readings for this thread there’s hasn’t been much sample variation at such high densities. So I doubt random variation as an explanation for the large difference between my readings and yours, and am at a loss to understand it.


#7

p.s. I initially read your Yahoo post and so missed this statement in the blog post: “[I]We are measuring at the 80% density patch because this is actually the maximum amount of ink we print as well as would Epson print using their RGB or ABW driver[/I]”. I hadn’t done this, I had measured at 100%, hence my comments above about not having allowed for density loss from overloading. So I went back and printed three bars of the shade 1 strip from the ink separation chart in calibration mode. Here are the average results for WN Opaque 1 on HPR:

[TABLE=“width: 250”]

Step
Ave Dens1
Ave Dens 2

100
1.646
1.654

95
1.655
1.668

90
1.646
1.656

85
1.644
1.652

80
1.637
1.646

75
1.623
1.630

70
1.615
1.621

65
1.596
1.604

60
1.585
1.594

[/TABLE]
[I]* Ave Density 1 was after blow drying and 4 hours air drying

  • Ave Density 2 was after an additional 8 hours air drying[/I]

These numbers are a bit lower than yesterday - not sure why. They were printed slightly differently in terms of patch size and direction. Perhaps they need more drying time - even though they were dried with a hair dryer then left for several hours. I’ll check them again in the morning. [I]p.s. the morning results were a bit higher and closer to my previous results.[/I]

But the point remains that they’re nowhere near the number you quote on that black is black page and they’re still fairly close to your number for Selenium 1. So my doubt about your 1.409 remains.


#8

At the risk of appearing obsessive, I’ve updated these numbers after further drying time.


#9

Hi Brian~

I am re-evaluating the black ink tests we did, and going over the numerous measurements we did of each ink/paper combination. What I’m finding is it’s hard to get consistent results with the EyeOne patch measurement over time (there’s a range from measurements taken on 7/17/14, 10/9/14 and today).
Today, I measured them all again with our densitometer and EyeOne. I like the EyeOne with Measure Tool, because it gives Lab values, but feel like I get more consistent readings with the densitometer (yes, both instruments are calibrated before each use). Today, with the densitometer, I measured 1.60 at the 60% patch of WN#1 (the same lot# you’re using) on Hahnemuhle Photo Rag, so am getting about the same results as you. I don’t want to fully publish all my new measurements, until I review them with Jon next week.

Jon and Kelly have left for the day, and I’m leaving tomorrow for a family trip, so won’t be back in the office till Tuesday afternoon (if I’m not drained after traveling). Depending on everything that’s going on when I return, I’ll review my findings with them at some point next week, and may have an update after our conversation and evaluation of all my measurements over the last several months.

Best regards and happy printing~ Dana :slight_smile:


#10

No rush. Safe travels.

p.s. I agree that is is hard to get completely consistent readings, at least with my EyeOne Pro (v1). Especially if you’re after very precise measurements of dmax for comparative purposes. That doesn’t overly concern me. Despite the impression that the last few posts might have created, I don’t want to obsess over small to smallish measured variations in shade 1 dmax. Especially as what you get in practice is a combination of at least 4 shades, as Jon pointed out, and also given that piezo is not really about dmax.

But there is quite a large difference between 1.64-1.66 and 1.409. That concerns me.


#11

Dana - did you come to any conclusion on this? I see that the blog post still has that that suspect 1.409 number.